---
title: "Find the Mistake Level Up #17: 3 Sudoku Levels | Sudoku Flow"
description: "Three Sudoku boards, one wrong number in each: a 4×4, a 6×6, then a full 9×9. Level Up #17: play every level and see each answer."
url: https://sudokuflow.com/puzzles/level-up-17/
language: en
---
[Puzzles](https://sudokuflow.com/puzzles/) / Level Up #17
Level Up
# Level Up #17
Three boards, each with one wrong number, from a small 4×4 to a full 9×9. Play every level here, at your own pace.
[Watch on YouTube](https://youtube.com/shorts/6R4DCVQLMqo)
## Level 1 · 4×4
Tap the digit you think is wrong.
Level Up #17 · Level 1 · 4×4:
```text
4* 2 | . .
. 3* | 4 2
------+------
3 4 | 2 3*
. 1* | . 4*
```
Digits marked * were filled in by a player; the others were printed with the puzzle.
Show the answer
It's the blue 3 in row 3, column 4. Row 3 already has a printed 3 (row 3, column 1). A printed digit can't be wrong, so the blue one is. The right digit for that cell is 1.
## Level 2 · 6×6
Tap the digit you think is wrong.
Level Up #17 · Level 2 · 6×6:
```text
1* 6 4* | 3* . .
2* 3 5 | . 1* 4
---------+---------
. 1 . | 5* 4 .
5 . 6* | 2 3 1*
---------+---------
4 5 3* | . 6* .
6 1* . | 4 5 3
```
Digits marked * were filled in by a player; the others were printed with the puzzle.
Show the answer
It's the blue 1 in row 6, column 2. Column 2 already has a printed 1 (row 3, column 2). A printed digit can't be wrong, so the blue one is. The right digit for that cell is 2.
## Level 3 · 9×9
Tap the digit you think is wrong.
Level Up #17 · Level 3 · 9×9:
```text
5 6 3 | 2* 9 4 | 7 8* 1*
2 9 4* | 7* . . | 5* 6 3
7* 8* 1 | 5* 3 6 | 2 9* 4
---------+----------+---------
6* 5* 7 | 1* 2* 9 | 3* 4 8*
3 2 9* | 8 4* 5* | 6 . 7
. . . | 3 . . | 9* . 2
---------+----------+---------
. . . | 4 . . | 1 . 6
. 7 . | 9 . 2 | 4 . 5*
1 . . | 6 5 . | 7* . 9
```
Digits marked * were filled in by a player; the others were printed with the puzzle.
Show the answer
It's the blue 7 in row 9, column 7. Column 7 already has a printed 7 (row 1, column 7). A printed digit can't be wrong, so the blue one is. The right digit for that cell is 8.
## Want more boards like this?
We also make a Sudoku app for iPhone, iPad, Mac and Android. There are no ads in it at all, it works offline, and when you ask for a hint it shows you the technique instead of just filling in a number.
[App Store iPhone, iPad, Mac](https://apps.apple.com/app/apple-store/id6502922368?pt=125379530&ct=sudokuflow_web&mt=8) [Google Play Android](https://play.google.com/store/apps/details?id=com.rubigogames.sudoku&referrer=utm_source%3Dsudokuflow%26utm_medium%3Dweb%26utm_campaign%3Dsite)
Sudoku Flow is made by Rubigo Games, the developer of the Sudoku app recommended on this site.